Features:
- High hardness and wear resistance, providing long tool life
- High thermal stability, allowing for use at high cutting speeds and temperatures. Can tolerate up to 1000 °C comfortably and can still retains cutting power at even higher temperatures, though at reduced lifespan
- Suitable for cutting hardened tool steel, cast iron and other high hardness ferrous metals.
- Good chemical stability, resisting wear and damage from cutting fluids and coolants
When not to use CBN:
CBN is unsuitable for cutting many softer metals, which can be cut equally well or better with cheaper carbide inserts. CBN is designed for hardness and temperature resistance, rather than sharpness, and so will not cut softer metals as well as a sharper, less hard material like uncoated carbide.
- Aluminium and Aluminium Alloys - CBN contains trace amounts of Aluminium Nitride which chemically reacts with aluminium which causes it to bond with the cutter, which both leaves a terrible surface finish and rapidly wears the cutter. For High Performance Aluminium cutting inserts look to uncoated Carbide or PCD inserts.
- Chromium and Chrome Alloys over 20% chromium content - CBN can cut chrome plated steels but pure chromium or alloys with high chromium content will chemically react with CBN to form Chromium Carbide which results in short tool lifespan.